We have developed techniques for reconstructing the three-dimensional morphology of the diaphragm muscle as a function of respiratory phase. These techniques fall into two categories, wide field of view images which permit us to define the overall morphology and action of the diaphragm, and high resolution images which permit us to image the diaphragm directly and measure its thickness. In patients with severe COLD, magnetic resonance (MR) imaging can effectively define the concomitant abnormality of diaphragmatic form and function and help to define the change in diaphragmatic mechanics which follows surgical reduction pneumoplasty. By appropriate choice of imaging parameters, we are able to characterize both the piston-like displacement of the diaphragm and its change in curvature. We have reason to believe that this population of patients is distinguished from the population of normals by diaphragm position, diaphragm shape, and change in both of these during the respiratory cycle. We plan to measure the diaphragmatic dysfunction, relative to the control group, in patients preparing to undergo the surgery aimed at improving pulmonary function. Having chosen parameters of diaphragm position, shape, displacement, and change in shape which distinguish the disease group from the normals, we plan to measure the subacute improvement in diaphragmatic function shortly following the surgery. In addition, we plan to restudy the patients eight weeks post-operatively in order to detect any chronic adaptation, such as muscle hypertrophy, which modifies the acute surgical alteration in diaphragm mechanics. Additional information about the state of the muscle can be inferred from values of T2 and the chemical shift, which provide information concerning muscle atrophy and fat content. These measurements will provide information on the physiological response of the diaphragm to the changes in form and work load caused by the surgery.